What are rules?

NoSpamProxy applies rules that you can configure individually when processing emails. These rules are modular in structure. You can create your own rules and modify existing rules by selecting the desired filters from the available filters for each individual rule. Within each rule you can weight and configure them as you wish using a multiplier.

You can also specify that rules apply only to specific IP addresses or recipients, for example, only to senders with a specific TLD (Top Level Domain) or IP addresses from a specific subnet.

TIP: After reinstalling NoSpamProxy, you can create default rules. These enable the gateway to start functioning as quickly as possible with minimal administration effort. Nevertheless, you should check these rules and adapt them to your needs if necessary.

The order of the rules is crucial

If a rule is responsible for an email to be checked, it will be used. If more than one rule applies to an email, the rule that is highest in the list is applied.

How rules, filters and actions are related

To process emails, NoSpamProxy applies rules that you can configure individually. For each email, the individual filters of the applicable rule are executed.Filters evaluate how strongly the email meets a certain filter criterion and award corresponding penalty and bonus points. The awarded points are weighted with the multiplier of the filters and then added to a total value. If this value exceeds the set Spam Confidence Level (SCL) of the rule, the email will be rejected. You can set the allowed SCL individually for each rule. See Configuring filters and Filters in NoSpamProxy.Actions in NoSpamProxy are called up after the filters have determined whether the email is rejected or allowed to pass. Actions can, among other things, modify the emails, for example to add a footer or remove unwanted attachments. However, actions can also reject emails that would actually happen after they have been evaluated by the filters. This means that a virus scanner, for example, can still reject the email even though it has not been detected as spam. Actions are therefore higher-level settings with which filters can be overridden if necessary. To find out which actions are available and how they work exactly, see Actions available in NoSpamProxy.

Creating rules

For information on creating rules, see Creating rules.